This is today's edition of The Download, our weekday newsletter that provides a daily dose of what's going on in the world of technology.

How Meta and AI companies recruited striking actors to train AI

Between July and September this year, actors in the US were invited to participate in an unusual research project, designed to capture their voices, faces, movements, and expressions.

The project, which coincided with Hollywood’s historic strikes by the Writers Guild of America and the Screen Actors Guild, was run by London-based emotion AI company Realeyes and Meta. The information captured from the actors was fed into an AI database to better understand and express human emotions. 

Many actors across the industry worry that AI could be used to replace them, whether or not their exact faces are copied. And in this case, by providing the facial expressions that will teach AI to appear more human, study participants may in fact have been the ones inadvertently training their own potential replacements. Read the full story.

—Eileen Guo

Inside the quest for unbreakable encryption

When we check our email inbox, log in to our bank accounts, or message on Signal, our passwords and credentials are protected through encryption, a locking scheme that uses secrets to disguise our data. 

Our trust in online security is rooted in mathematics. Encryption schemes are built on families of math problems called one-way functions—calculations that are easy to carry out in one direction but almost impossible to solve efficiently from the other, even with a powerful computer. 

There’s a problem, however. Although mathematicians suspect true one-way functions exist, they’ve yet to prove it. This conundrum haunts all encryption. Our data is secured by the fact that no one knows how to crack the schemes that protect it—or at least not yet. Read the full story.

—Stephen Ornes

Stephen’s story is from the next magazine edition of MIT Technology Review, set to go live next Wednesday. It’s all about society’s hardest problems, and how we should tackle them. If you don’t subscribe already, sign up now to get a copy when it lands!

Plastic is a climate change problem. But there are ways to fix it.

Plastic is a huge problem. But there’s an often-overlooked angle to all this that goes beyond the familiar images of landfills. Plastics are a big, and quickly growing, issue for the climate. They account for about 3.4% of global greenhouse-gas emissions—more than the entire aviation industry. 

However, a combination of technology and policy could help to clean up our growing plastics problem. Casey Crownhart, our climate reporter, has dug into how plastic contributes to greenhouse-gas emissions, and where we go from here. Read the full story.

This story first appeared in The Spark, our weekly climate and energy newsletter. Sign up to receive it in your inbox every Wednesday.

2023 Climate Tech Companies to Watch: GEM and its battery recycling factories

Building on two decades of experience in recycling batteries and electronics, GEM is doing the essential work of making electric vehicle batteries greener, giving them a second life by repurposing them or extracting the minerals they contain. Read more about GEM, and check out the rest of the list of Climate Tech Companies to Watch.

The must-reads

I’ve combed the internet to find you today’s most fun/important/scary/fascinating stories about technology.

1 Instagram removed an image of the Gaza hospital bombing
Users are complaining that their posts are being deleted and searches blocked in relation to the Israel-Hamas conflict. (The Intercept)
+ Pseudo-OSINT accounts are taking over X. (404 Media)
+ Meta is limiting comments on posts linked to the conflict, too. (Reuters)

2 Grieving parents are suing Snapchat 
Their children died after buying drugs on the platform. But not all bereaved parents agree that taking legal action is the right course. (The Guardian)

3 India is deploying internet blackouts to control its citizens 
Even more frequently than Russia or China. (WP $)
+ Why you should be more concerned about internet shutdowns. (MIT Technology Review)

4 Amazon’s warehouses have been overhauled with robotics and AI
The steady march of tech is making the company’s human workers feel nervous. (WSJ $)
+ Humans are less likely to pay attention when working with robots, apparently. (The Guardian)
+ Amazon is finally expanding its drone delivery program. (The Verge)

5 Apple has fired App Store workers over their conduct
For accepting unsanctioned meals and outings footed by games developers. (The Information $)

6 The Ozempic effect is coming for all sorts of conditions
The more approved uses for a drug, the more financially lucrative it is for the maker. (Bloomberg $)
+ Weight-loss injections have taken over the internet. But what does this mean for people IRL? (MIT Technology Review)

7 How to keep nuclear weapons safe 
The US’s nuclear arsenal is aging. Could supercomputers help? (IEEE Spectrum)

8 The bright promise of space-based solar power ☀️
The sun is basically an infinite energy resource. Why not harness it? (FT $)
+ The world is finally spending more on solar than oil production. (MIT Technology Review)

9 What it’s like to turn words into music
Simply tell AI to translate ‘light-up dancefloor grooves’ into a tune, sit back and listen. (Pitchfork)
+ Want to sing like Drake? YouTube’s got a tool for that. (Bloomberg $)
+ Record label Universal Music is suing Anthropic over its AI lyrics. (FT $)
+ A Disney director tried—and failed—to use an AI Hans Zimmer to create a soundtrack. (MIT Technology Review)

10 Supermarkets’ self-checkout still sucks
Not another unexpected item in the bagging area! (The Atlantic $)

Quote of the day

“Companies try to release AI for good uses and keep its unlawful uses behind a locked door. But no one knows how to make a lock.”

—Scott Emmons, a researcher at the University of California, reflects on the complexities of creating effective guardrails for AI to the New York Times.

The big story

Should we believe in—or even want—immortality?

October 2022

Twenty years have passed since writer Jonathan Weiner first met Aubrey de Grey. Back then, Aubrey was already a True Believer in the quest for immortality. And he wasn’t yet a man in disgrace.

Weiner first met Aubrey in 2002, when Aubrey was still working as a computer programmer in the Department of Genetics at the University of Cambridge. He rapidly became a secular guru, a prophet of immortality—to the intense annoyance of most of the scientists in the aging field. 

But Aubrey’s eagerness to convince believers they could live for centuries, millennia, or even longer, raises pertinent questions about what it is to want something we may not even believe in. Read the full story.

We can still have nice things

A place for comfort, fun and distraction in these weird times. (Got any ideas? Drop me a line or tweet 'em at me.)

+ These teeny-tiny miniatures are incredibly cute.
+ Meanwhile, in London, they’re hanging a bale of hay from one of the city’s most prominent bridges.
+ System of a Down’s Chop Suey—with added table.
+ Phew, Pepper X sounds like a real scorcher. 🌶️
+ Make way for Bella the cat, who has the Guiness world record for the world’s loudest purr.